article | report | letter | chapter | section | subsection | subsubsection | paragraph | subparagraph | summary | notice | colophon | group | p | theorem | proof | blockquote | item | theglossary | references | index
(#PCDATA | em | visual | verb | style | lettrine | m | math? | ch | latex | url | hspace | unit | relax | wrap | quote | newline | mnote | cite | pageref | vpageref | ref | vref | gloss | mathref | footnote | ix | idx | indexsee | graphics)*
The h element provides a heading that is not tied to document structure in the way that section, subsection, etc are. The level attribute must be an integer between 1 and 6; these roughly correspond to XHTML’s <h1> … <h6>. The special value 0 is used to generate an unnumbered chapter heading in the references for a book.